Generally, a conventional data I/O apparatus is implemented by the same structure as the internal structure of a so-called PC (personal computer) using a microprocessor, in which a hard disk is connected to a processor bus. In order to efficiently read and write data by using a plurality of storage apparatuses, the data is migrated to a proper storage apparatus by perfectly copying the data. As one example of this technique, see Japanese Patent Laid-Open No. 2001-337790.
As described above, recently, a high-resolution moving image such as an HDTV image has become widely used. Accordingly, the need for efficiently implementing a storage or broadcast system, which stores/broadcasts information that requires a broad bandwidth has received a great deal of attention.
However, as the high-resolution moving image such as an HDTV image is used more widely, a broader bandwidth is required to transmit the data from a storage unit. As a result, when a plurality of contents are to be simultaneously read out, the bandwidth sometimes becomes insufficient. Accordingly, all the required contents cannot be enjoyed, thus posing a problem. In order to solve this problem, an expensive storage unit having a broad bandwidth must be used, thus increasing the cost.